US4289223A - Shiftable friction clutch for gear drives - Google Patents

Shiftable friction clutch for gear drives Download PDF

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Publication number
US4289223A
US4289223A US06/041,923 US4192379A US4289223A US 4289223 A US4289223 A US 4289223A US 4192379 A US4192379 A US 4192379A US 4289223 A US4289223 A US 4289223A
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US
United States
Prior art keywords
clutch
friction
carrier sleeve
shaft
axially
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US06/041,923
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English (en)
Inventor
Richard Strehler
Max Bartl
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ZF-HURTH MARINE SpA
Original Assignee
Carl Hurth Maschinen und Zahnradfabrik GmbH and Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
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Application filed by Carl Hurth Maschinen und Zahnradfabrik GmbH and Co filed Critical Carl Hurth Maschinen und Zahnradfabrik GmbH and Co
Assigned to CARL HURTH MACHINEN- UND ZAHNRADFABRIK GMBH & CO. reassignment CARL HURTH MACHINEN- UND ZAHNRADFABRIK GMBH & CO. CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). EFFECTIVE DATE 1-22-81 Assignors: CARL HURTH MASCHINEN-UND ZAHNRADFABRIK
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Publication of US4289223A publication Critical patent/US4289223A/en
Assigned to HURTH GETRIEBE UND ZAHNRAEDER G.M.B.H. reassignment HURTH GETRIEBE UND ZAHNRAEDER G.M.B.H. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: CARL HURTH MASCHINEN- UND ZAHNRADFABRIK GMBH
Assigned to ZF-HURTH MARINE S.P.A. reassignment ZF-HURTH MARINE S.P.A. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HURTH GETRIEBE UND ZAHNRAEDER G.M.B.H.
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D7/00Slip couplings, e.g. slipping on overload, for absorbing shock
    • F16D7/02Slip couplings, e.g. slipping on overload, for absorbing shock of the friction type
    • F16D7/024Slip couplings, e.g. slipping on overload, for absorbing shock of the friction type with axially applied torque limiting friction surfaces
    • F16D7/028Slip couplings, e.g. slipping on overload, for absorbing shock of the friction type with axially applied torque limiting friction surfaces with conical friction surfaces
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D13/00Friction clutches
    • F16D13/04Friction clutches with means for actuating or keeping engaged by a force derived at least partially from one of the shafts to be connected
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D13/00Friction clutches
    • F16D13/22Friction clutches with axially-movable clutching members
    • F16D13/24Friction clutches with axially-movable clutching members with conical friction surfaces cone clutches
    • F16D13/26Friction clutches with axially-movable clutching members with conical friction surfaces cone clutches in which the or each axially-movable member is pressed exclusively against an axially-located member
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D21/00Systems comprising a plurality of actuated clutches
    • F16D21/02Systems comprising a plurality of actuated clutches for interconnecting three or more shafts or other transmission members in different ways
    • F16D21/04Systems comprising a plurality of actuated clutches for interconnecting three or more shafts or other transmission members in different ways with a shaft carrying a number of rotatable transmission members, e.g. gears, each of which can be connected to the shaft by a clutching member or members between the shaft and the hub of the transmission member
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D47/00Systems of clutches, or clutches and couplings, comprising devices of types grouped under at least two of the preceding guide headings
    • F16D47/02Systems of clutches, or clutches and couplings, comprising devices of types grouped under at least two of the preceding guide headings of which at least one is a coupling

Definitions

  • This invention relates to a shiftable friction clutch for use particularly in driving gears.
  • a friction clutch of this type is known from German Auslegeschrift No. 16 25 849, first published on Aug. 20, 1970, in which the spring for the safety clutch is arranged in the power flow - viewed from the clutch pack - behind the gear which must be coupled, so that when the safety clutch becomes effective, the gear must move.
  • the safety clutch is burdened with the mass of the gear, which can lead to difficulties during shifting, which are noticed externally by a chatter noise during shifting.
  • the basic purpose of the invention is to provide a friction clutch of the above-described type, which has at a relatively small assembled length still only small masses which act onto the spring.
  • the carrier sleeve being mounted axially movably on the shaft and the supporting spring being arranged on the side of the carrier sleeve remote from the clutch friction surfaces, between the carrier sleeve and the shaft or between the carrier sleeve and a part which is fixedly connected to the shaft.
  • two stops are arranged as is actually known, to limit the axial movement of the friction ring in direction of the clutch engagement of which stops the first is effective until the torque is exceeded and the second during an exceeding of the maximum permissible torque.
  • a preferable development of the invention is achieved, when the second stop is arranged acting in peripheral direction. Stops which act in peripheral direction are known.
  • the friction ring which is supported through rolling elements on the guide sleeve carries out a helical movement, that is, a movement in both the axial direction and the peripheral direction.
  • the stop which acts in peripheral direction prevents a jamming of the rolling elements or of the friction ring at high torque.
  • the invention becomes particularly advantageous with an arrangement of the spring in the annular space which is formed by the carrier sleeve, shaft, gear and clutch element to thereby provide a compact solution.
  • FIG. 1 is a longitudinal cross-sectional view of a clutch according to the invention
  • FIG. 2 is a cross-sectional view of the stop device according to the invention.
  • FIG. 3 is a partial cross-sectional view of the rolling elements lying between inclined planes.
  • FIG. 4 is a cross-sectional view taken along the line IV--IV of FIG. 1 and illustrates schematically a phase during the shifting cycle.
  • FIG. 1 illustrates as an exemplary embodiment a double clutch having conical friction surfaces.
  • a shaft 1 is to be selectively connected through a friction coupling to the gears 2, 3, which are rotatably supported on the shaft and are held against axial movement by suitable means, for example by plates 4 or a shoulder 5.
  • a carrier sleeve 7 is slidably mounted on the shaft 1 and is axially movable between the two gears. The carrier sleeve is fixed against rotation relative to the shaft 1 by at least one adjusting spring 6. The carrier sleeve will be discussed in more detail below.
  • a shift collar 8 is longitudinally movably guided on the carrier sleeve. The shift collar 8 is secured against rotation relative to the carrier sleeve by not shown conventional means.
  • a friction ring 9, 10 is concentrically arranged to the axis of rotation on each side of the carrier sleeve.
  • the outside diameter of the friction rings corresponds approximately to the outside diameter of the carrier sleeve.
  • the friction rings each have an inner conical surface 11, 12 which cooperates with an adjacent outer conical surface 13, 14 on the gears 2, 3.
  • the friction rings 9, 10 and the carrier sleeve 7 have milled recesses 40, 41 on the sides facing one another (FIG. 3). Said milled recesses each have two flat inclined planar surfaces 42, 43, 44, 45. Balls 46 lie therebetween and function as rolling elements. When one friction ring and the carrier sleeve are relatively rotated with respect to one another, the balls 46 run onto the flat inclined planes, which thus serve as a ramp, and thereby urge the friction ring away from the carrier sleeve, which causes the aforementioned cones to be pressed into engagement with one another.
  • the connected gear is coupled through its outer conical surface, the associated inner conical surface, the respective friction ring, the respective balls and the carrier sleeve 7 to the shaft 1.
  • the milled recesses can also be inclined such that the rolling elements can run only in one direction of rotation onto the ramp surface.
  • the friction rings 9, 10 are urged by one or several return springs 25 (FIG. 4) toward the carrier sleeve, which are arranged on the periphery of the friction rings and are constructed as coiled flat springs, so-called hairpin or torsion springs. Projections are provided on the periphery of the friction rings for supporting these springs.
  • the shift collar 8 includes a sleeve member 23, which is provided on the radially outer periphery thereof with an annular groove 24 for receiving a conventional, hence not shown, gearshift fork therein.
  • the sleeve member 23 has on the axially facing sides thereof two inclined surfaces which converge toward the center, which surfaces are called first pressure surfaces 26, 26'.
  • first pressure surfaces 26, 26' When the planar surfaces, for example 42, of the friction members, which surfaces serve as a ramp for the rolling elements, are sloped in a certain peripheral direction, enlarging the milled recesses 40, 41, then the first pressure surfaces 26, 26' taper in the same direction toward each other and may come together in the central plane (rotation plane) of the sleeve member.
  • Openings 27 follow the part of the sleeve member which forms the first pressure surfaces, which openings receive the mentioned return springs 25.
  • Blockers 28, 28' are provided on the sleeve member at an axial distance from the first pressure surfaces 26, 26' and form on the side which faces the first pressure surfaces countersurfaces or second pressure surfaces 33, 33' which are parallel with the first pressure surfaces.
  • the sleeve member and the blocks thus form inwardly open grooves 29, 29'.
  • Teeth 30, 30' are provided on the periphery of the friction members, which teeth are each provided on the side facing the sleeve member 23 with a counter pressure surface 37, 37', which extend parallel with respect to the aforementioned first pressure surfaces 26, 26' on the sleeve member.
  • Each tooth has on the other side a countersurface 38, 38', which extends parallel with respect to the facing countersurface 33, 33' on the blocker.
  • the grooves 29, 29' are wider in axial direction than the teeth 30, 30'.
  • the teeth have a stop surface 34, 34' approximately in a plane which extends through the axis of rotation and on the side which faces the blocker, which surface is directed approximately at a right angle with respect to the plane of rotation (direction of rotation).
  • the blockers 28, 28' On the side which faces the teeth, the blockers 28, 28' have a stop surface 39, 39', which is also directed approximately at a right angle with respect to the plane of rotation.
  • the first pressure surfaces, for example 26 is urged onto the counter pressure surface, for example 37, and, as a result, the rotating friction ring 10 is moved toward and into engagement with the friction surface 12 on the gear 3 to cause the transmission of torque to be started.
  • the transmittable torque is thereafter increased by the balls 46 which are caused to run onto the ramps when a relative rotation occurs between the friction ring 10 and carrier sleeve 7.
  • Disengagement of the clutch is done by urging the countersurfaces of the sleeve member onto the countersurface of the friction ring. The cooperation of the stop surfaces 39, 39' with the stop surfaces 34, 34' prevents the disengaged friction ring 9 from being engaged unintentionally.
  • a latch pin 32 which is loaded by a spring is radially movably guided in the carrier sleeve 7.
  • a recess for locking the gearshift sleeve in the disengaged condition (neutral position) is provided in the center of the sleeve member.
  • Two locking openings which are open toward the side, thus are half locking openings, or inclined surfaces 31, 31' are provided on the front sides of the gearshift sleeve for fixing the two starting conditions.
  • the latch pin 32 and the inclined surfaces 31, 31' on the front sides of the gearshift sleeve member support the starting operation.
  • the carrier sleeve 7 is, as already mentioned, axially movable on the shaft 1. It is held in its neutral position by two snap rings 15, 16 which are placed with little radial clearance in annular grooves 17, 18 in the shaft 1. The grooves are wider than the snap rings and the distance a between their lateral limits which face the carrier sleeve corresponds substantially with the width of the carrier sleeve. Belleville springs 19, 20 engage on one side thereof the side of the snap rings remote from the carrier sleeve, and engage on the other side a plate 21, 22 which axially guides the gear 2, 3. The effect of the Belleville springs will be discussed below.
  • the carrier sleeve 7 has, as illustrated in FIG.
  • the maximum friction force and thus the maximum transmittable torque thus depends on the force of the springs 19 or 20. If during an engagement function the respective friction ring, for example 10, is supported by the balls 46 on the carrier sleeve 7, then the carrier sleeve yields to the force of the Belleville springs 19, in FIG. 1 thus to the right. The friction ring 10 is thus loaded by the Belleville springs 19 in the sense of an engagement.
  • the Belleville springs 20 remain hereby without importance, because their initial force does not change during the yielding of the carrier sleeve to the right, because the snap ring 16 rests on the groove wall. As a result, it is assured that a defined force acts from the Belleville springs 19 onto the friction surfaces (conical surfaces 12, 14) and only the Belleville springs 19 are decisive for the maximum transmittable torque.
  • the clutch shifts very softly, namely without chatter, because the initial tension force of the Belleville springs 19, 20 is influenced only by small mass forces, in particular the mass of the gears 2 and 3 is kept away from the Belleville springs.
  • the described clutch is built very compactly, because the Belleville springs are housed within the actual cone clutch construction, namely the Belleville springs 19, 20 are surrounded with a radial clearance by the parts 2', 3' of the gears 2, 3, which parts have the outer conical surfaces 13, 14.
  • the invention is not limited to the above example of use. It can be applied among others also in one-sided clutches or in multiple disk clutches. Furthermore, the design of the individual structural parts as for example the stops, the friction surfaces, etc. is not limited to the described and/or illustrated embodiment.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Mechanical Operated Clutches (AREA)
US06/041,923 1978-06-30 1979-05-24 Shiftable friction clutch for gear drives Expired - Lifetime US4289223A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE2828722 1978-06-30
DE19782828722 DE2828722A1 (de) 1978-06-30 1978-06-30 Schaltbare reibungskupplung fuer zahnradgetriebe

Publications (1)

Publication Number Publication Date
US4289223A true US4289223A (en) 1981-09-15

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ID=6043178

Family Applications (1)

Application Number Title Priority Date Filing Date
US06/041,923 Expired - Lifetime US4289223A (en) 1978-06-30 1979-05-24 Shiftable friction clutch for gear drives

Country Status (10)

Country Link
US (1) US4289223A (ru)
JP (1) JPS5510175A (ru)
BR (1) BR7902396A (ru)
DE (1) DE2828722A1 (ru)
ES (1) ES8100025A1 (ru)
FR (1) FR2429937A1 (ru)
GB (1) GB2024341A (ru)
IT (1) IT1203229B (ru)
SE (1) SE7813053L (ru)
SU (1) SU826974A3 (ru)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4370902A (en) * 1979-09-28 1983-02-01 Rotork Controls Limited Drive mechanisms, more particularly for valve actuators
US4534236A (en) * 1983-03-15 1985-08-13 Honda Giken Kogyo Kabushiki Kaisha Vibration and noise reduction means for a transmission vehicle
US5083993A (en) * 1989-10-19 1992-01-28 Saab Scania Aktiebolag Synchronizing arrangement for a planetary gear
WO1995014179A1 (en) * 1993-11-18 1995-05-26 Ab Volvo Synchronizing device in a vehicle gearbox
US6443281B2 (en) 1999-12-08 2002-09-03 Eaton Corporation Synchronizer
US6467598B2 (en) 1999-12-08 2002-10-22 Eaton Corporation Synchronizer
US20050202920A1 (en) * 2004-03-12 2005-09-15 Borgwarner Inc. Transfer case with torque synchronizer clutching
DE10302236B4 (de) * 2003-01-20 2012-12-06 Zf Friedrichshafen Ag Reibungskupplung oder Reibungsbremse mit Selbstverstärkung
CN110131029A (zh) * 2018-02-08 2019-08-16 河南德昌机械制造有限公司 一种正反转风扇自动清理水箱装置

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE425650B (sv) * 1981-03-05 1982-10-25 Volvo Penta Ab Transmission, isynnerhet for batmotorer
DE3623142A1 (de) * 1986-07-09 1988-01-28 Hurth Masch Zahnrad Carl Schaltbare reibungskupplung fuer zahnradgetriebe
DE4302083A1 (de) * 1993-01-19 1994-07-21 Black & Decker Inc Kraftgetriebenes Werkzeug, insbesondere Elektrowerkzeug
DE102010029863A1 (de) * 2010-06-09 2011-12-15 Zf Friedrichshafen Ag Lösbare axiale Fixierung zweier Bauteile
DE102014108202A1 (de) * 2014-06-11 2015-12-17 Hoerbiger Antriebstechnik Holding Gmbh Synchronisationseinheit für ein Getriebe

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2546712A (en) * 1947-08-30 1951-03-27 Int Harvester Co Sprag type synchronizer device
US2874817A (en) * 1955-02-23 1959-02-24 Daimler Benz Ag Friction clutch with torque responsive lock
US3189147A (en) * 1961-09-11 1965-06-15 Borg Warner Multiple clutch with lever
US3203525A (en) * 1962-03-21 1965-08-31 Zahnradfabrik Friedrichshafen Friction clutch
US3703226A (en) * 1970-09-14 1972-11-21 Hurth Masch Zahnrad Carl Shiftable friction clutch
US4118996A (en) * 1976-04-06 1978-10-10 Carl Hurth Maschinen- Und Zahnradfabrik Reversing gear in particular for a Z-drive for watercrafts

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2546712A (en) * 1947-08-30 1951-03-27 Int Harvester Co Sprag type synchronizer device
US2874817A (en) * 1955-02-23 1959-02-24 Daimler Benz Ag Friction clutch with torque responsive lock
US3189147A (en) * 1961-09-11 1965-06-15 Borg Warner Multiple clutch with lever
US3203525A (en) * 1962-03-21 1965-08-31 Zahnradfabrik Friedrichshafen Friction clutch
US3703226A (en) * 1970-09-14 1972-11-21 Hurth Masch Zahnrad Carl Shiftable friction clutch
US4118996A (en) * 1976-04-06 1978-10-10 Carl Hurth Maschinen- Und Zahnradfabrik Reversing gear in particular for a Z-drive for watercrafts

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4370902A (en) * 1979-09-28 1983-02-01 Rotork Controls Limited Drive mechanisms, more particularly for valve actuators
US4534236A (en) * 1983-03-15 1985-08-13 Honda Giken Kogyo Kabushiki Kaisha Vibration and noise reduction means for a transmission vehicle
US5083993A (en) * 1989-10-19 1992-01-28 Saab Scania Aktiebolag Synchronizing arrangement for a planetary gear
WO1995014179A1 (en) * 1993-11-18 1995-05-26 Ab Volvo Synchronizing device in a vehicle gearbox
US5678670A (en) * 1993-11-18 1997-10-21 Volvo Lastvagnar Ab Synchronizing device in a vehicle gearbox
CN1046340C (zh) * 1993-11-18 1999-11-10 沃尔沃·拉斯特韦格纳公司 车辆齿轮箱中的同步装置
US6443281B2 (en) 1999-12-08 2002-09-03 Eaton Corporation Synchronizer
US6467598B2 (en) 1999-12-08 2002-10-22 Eaton Corporation Synchronizer
DE10302236B4 (de) * 2003-01-20 2012-12-06 Zf Friedrichshafen Ag Reibungskupplung oder Reibungsbremse mit Selbstverstärkung
US20050202920A1 (en) * 2004-03-12 2005-09-15 Borgwarner Inc. Transfer case with torque synchronizer clutching
US7384366B2 (en) 2004-03-12 2008-06-10 Borgwarner Inc. Transfer case with torque synchronizer clutching
CN110131029A (zh) * 2018-02-08 2019-08-16 河南德昌机械制造有限公司 一种正反转风扇自动清理水箱装置
CN110131029B (zh) * 2018-02-08 2020-07-21 河南德昌机械制造有限公司 一种正反转风扇自动清理水箱装置

Also Published As

Publication number Publication date
SU826974A3 (ru) 1981-04-30
FR2429937A1 (fr) 1980-01-25
ES482079A0 (es) 1980-04-01
IT1203229B (it) 1989-02-15
BR7902396A (pt) 1980-10-29
DE2828722A1 (de) 1980-01-10
GB2024341A (en) 1980-01-09
JPS5510175A (en) 1980-01-24
ES8100025A1 (es) 1980-04-01
IT7947724A0 (it) 1979-01-22
SE7813053L (sv) 1979-12-31

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Effective date: 19950706